It is known to process containers using rotary machines arranged to move the containers to be processed in rotation on wheels while performing one or more processes on the containers.
When the containers have to be subjected to more than one process, the rotary machine for example comprises successive wheels moving in rotation along parallel axes, each carrying stations arranged to perform one of the processes. The containers are moved through the machine, from one wheel to the next, and are each received in one station of each wheel where they are subjected to one process while they move in rotation on each wheel. Such machines offer a satisfactory throughput of processed containers since the processes are carried out in parallel, one wheel performing one process on a set of containers while another wheel preforms another process on another set of containers. The processes are therefore performed in parallel on different sets of containers.
However, such machines are very space consuming since the wheels have to be arranged one next to the other. Furthermore, when one of the processes is a filling process during which the containers are filled with a liquid, chances are high that liquid is spilled out of the containers under the influence of the centrifugal forces applied on the containers while they move in rotation or when their direction of rotation changes when they move from one wheel to the next.
In order to solve this problem, the containers have to be closed, for example by a cap, as soon as possible after they have been filled.
In order to do so, it has been proposed, as described in FIG. 2A of WO2013/020885, to perform the filling of the containers and the closing of said containers on the same wheel. In this case, the containers are subjected to a filling process in a first part of the rotational path of the wheel and are subjected to a closing process in the second part of the rotational path of the wheel. Consequently, the closing occurs immediately after the filling and the risks of spilling are reduced. However, the stations used for performing the filling process cannot be used at the same time for the closing process and conversely the stations used for performing the closing cannot be used at the same time for performing the filling process. The processes are consequently performed sequentially rather than in parallel. The number of stations performing the filling process and the number of stations performing the closing process are therefore reduced and the throughput of the machine decreases.
The same drawbacks remain for other processes than filling and closing containers. For example, filling containers should occur immediately after decontaminating said containers.
Document U.S. Pat. No. 6,152,723 discloses a rotary machine for first heating preforms and then blowing the preforms into containers. These processes are performed in parallel by rotating the preforms around a main axis in first stations arranged to heat the preforms, by moving the preforms from the first stations to second stations and by rotating them around the main axis in the second stations arranged to blow the preforms into containers. In the first stations, the preforms are moved in an upside down configuration, i.e. with their open end turned downwards. The preforms are moved to the second stations in this configuration or are turned between the upside down configuration and an upward configuration during the transfer to the second stations.
Document DE-10 2010 002246 discloses a rotary machine for first blowing preforms into containers and then labelling the blown containers. These processes are performed in parallel by rotating the preforms around a main axis in first stations arranged to blow the preforms into containers, by moving the formed containers from the first stations to second stations and by rotating them around the main axis in the second stations arranged to label the containers.
In these rotary machines, the processed containers, i.e. the heated preforms in U.S. Pat. No. 6,152,723 and the blown containers in DE-10 2010 002246, are moved to the second stations while they are empty. Consequently, the transfer of the processed containers between the first and second stations is not particularly problematic but would not be adapted if the processed containers were filled with a liquid.
One of the aims of the invention is to overcome the drawbacks mentioned above, by proposing a machine for processing containers, wherein several processes can be performed in parallel while reducing the space requirement of the machine and while preventing any spilling of the content of the containers during the transfer of the containers between first stations, wherein the containers are filled with a liquid, and second station, wherein the containers are subjected to another process.